問題詳情
211.Given: 11. public class Key{ 12. private long id1, 13. private long id2； 14. 15. //class Key methods 16. } A programmer is developing a class Key, that will be used as a key in a standard java.util.HashMap.Which two methods should be overridden to assure that Key works correctly as a key? (Choose two.)
(A) public int hashCode()
(B) public void hashCode()
(C) public int compareTo(Object o)
(D) public boolean equals(Object o)
(E)public boolean compareTo(Key k)
參考答案